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Railroad Commission of Texas. Victor G. Carrillo - Chairman Elizabeth A. Jones – Commissioner Michael L. Williams – Commissioner. Commercial Salt Water Disposal Well Permitting. Gil Bujano P.E. Assistant Director Technical Permitting, Oil & Gas Division. Regulatory Background.
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Railroad Commission of Texas Victor G. Carrillo - Chairman Elizabeth A. Jones – Commissioner Michael L. Williams – Commissioner
Commercial Salt Water Disposal Well Permitting Gil Bujano P.E. Assistant Director Technical Permitting, Oil & Gas Division
Regulatory Background • There are over 392,000 oil and gas industry wells in Texas • The first injection well in Texas was permitted in 1936 • There are 100,270 injection and disposal wells “on the books” • There are 52,084 currently permitted injection and disposal wells as of 1/6/2010
Regulatory Background • The RRC administers the Class II UIC program in Texas under authority delegated by EPA • 20% of UIC funding comes from EPA • EPA oversight is ongoing to ensure that the RRC program is effective • RRC program must be “equivalent” to EPA, but not necessarily identical.
Clay – 1 Comanche – 1 Cooke – 7 Denton – 3 Erath – 2 Grayson - 0 Hamilton – 2 Hill – 3 Hood - 16 Hamilton – 1 Jack – 15 Johnson – 28 Montague – 21 Palo Pinto – 10 Parker – 15 Somervell – 5 Tarrant – 4 Wise – 31 Over 160 Commercial Disposal Wells in the General Area
Permitting Staff • 4 Engineer/Geologists review permit applications • 1 Engineer supervises workgroup • 1 Engineer supervises the Technical Permitting section and signs all permits
General Permitting Requirements • Base of Useable Quality Groundwater depth • Notice and Hearing Opportunity • Area of Review • Geologic Requirements • Surface Casing • Production Casing • Packer Requirements
BUQW • For new wells, surface casing must be set to the protection depth determined by the Texas Commission on Environmental Quality (TCEQ) • This is called the Base of Useable Quality Water • The surface casing is cemented to the surface.
Notice & Hearing • surface owner • adjacent landowners (Commercial Disposal) • operators within ½ mile • city clerk if in city limits • published in general circulation paper • Protest: affected person who has or will suffer actual injury or economic damages other than a member of the general public…including surface owners and adjoining offset operators”
Area Of Review • Statewide rules require that an applicant for an injection or disposal well permit examine the data of record for wells that penetrate the proposed injection zone within a one quarter (1/4) mile radius of the proposed well • This is to determine if all abandoned wells have been plugged in a manner that will prevent the movement of fluids into strata other than the authorized injection or disposal zone. • A permit applicant must submit a map showing the location of all wells.
Geological Requirements • This part of the permit review verifies that the proposed injection zone is adequately isolated by relatively impermeable strata to confine injected fluids to the proposed zone. • The authorized injection or disposal strata must be isolated from overlying usable quality water by a sufficient thickness of relatively impermeable strata, which is generally considered to be an accumulative total of at least 250 feet of clay or shale.
Completion Requirements Three “Layers” of Protection • 1st Layer: Surface Casing • 2nd Layer: Production casing • 3rd Layer: Tubing and Packer
Surface Casing: 1st layer of protection • SWR 13 applies to all RRC wells and requires that surface casing be set and cemented through the groundwater to protect it before drilling beyond that depth into deeper formations • Surface casing acts as a protective sleeve through which the deeper drilling occurs
Production Casing Completion Requirements: 2nd layer of protection • SWR 13 applies to all RRC wells Requires production casing to be cemented with enough cement to fill 600 ft above shoe and any other productive intervals • SWR 9 applies to all RRC disposal wells Specifically for injection wells
Production Casing Completion Requirements cont… • After drilling (inside the surface casing) to the target formation, the production casing is set and cemented to isolate the target formation • SWR 9 Requires 400-600 ft. of cement at the top of the injection interval to ensure that injected fluids do not escape the permitted interval • By running bond logs, or temperature surveys to increase confidence in the effectiveness of the cement, less vertical cement may be permitted.
Tubing and Packer: 3rd layer of protection • All newly drilled or converted disposal wells permitted under Rule 9 must be equipped with tubing set on a mechanical packer unless an exception is granted by the director for good cause. Pressure observation valves are required on the tubing and each annulus.. • Tubing is slim pipe inserted into the center of the well bore inside the surface casing and production casing • A packer is a mechanical device that seals the open space (annulus) between the tubing and the packer • Disposal wells must have a packer set within 100 feet of the permitted disposal interval
Post-Permitting • Annual Monitoring reports must be filed on every injection/disposal well to report activity, status, and monitoring • 52,000 reports are received annualy and reviewed by staff and automated programs • Initial and periodic Mechanical Integrity Tests must be performed to check for leaks • RRC staff review 15,000 – 18,000 tests each year
Permitting of the Bosque Disposal Systems Sophia #3 • The well application was filed under Statewide Rule 9 for disposal of oil and gas exploration and production (E&P) waste into the interval between 8,700 and 12,750 feet below ground surface. • The well application is to dispose into the deeper Ellenburger formation, but would be carried in the shallower Barnet Shale for book keeping reasons.
Bosque Disposal Systems Sophia #3 Surface Casing • Deepest groundwater is at 1395 ft. at the well location • Rules require setting 1395 ft. of surface casing • Surface casing in the Sophia SWD well is to be set at 1,475 ft. and cemented back to ground surface